Automatic detection device and detection method for electronic control high-pressure common-rail fuel system

Abstract

The invention discloses an automatic detection device and method for an electronic control high-pressure common-rail fuel system. The automatic detection device comprises an upper computer system, a servo motor I, a servo motor II, a crankshaft signal panel, a camshaft signal panel and an injection detector. The output end of the upper computer system is in signal connection with the input end of the servo motor I and the input end of the servo motor II, the number of the injection detectors is the same as that of oil injectors in a fuel oil system, the injection detectors are connected with the corresponding oil injectors, and the output ends of the injection detectors are in signal connection with the input end of the upper computer system. An output signal interface of the upper computer system is connected with an ECU set rotating speed interface in the fuel system, the automatic detection device and the detection method of the electronic control high-pressure common-rail fuel system can achieve platform-level verification of the electronic control high-pressure common-rail fuel system, compared with installation verification, the risk of new product test run is avoided, and the energy cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of diesel engine testing technology, specifically to an electronically controlled high-pressure common rail fuel system automatic testing device and testing method. Background Technology

[0002] Traditional electronically controlled high-pressure common rail fuel system testing devices are mainly used for testing the performance of high-pressure fuel pumps, common rail pipes, and injectors. ECU testing is limited to ECU interface function testing and injector drive capability monitoring, but cannot realize the actual verification of ECU speed regulation capability and rail pressure regulation capability, thereby increasing the risk of new product testing and increasing energy costs. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the existing defects and provide an automatic testing device and testing method for an electronically controlled high-pressure common rail fuel system. This device and method can realize platform-level verification of the electronically controlled high-pressure common rail fuel system. Compared with on-machine verification, it avoids the risks of new product testing, reduces energy costs, and can effectively solve the problems in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an automatic detection device for an electronically controlled high-pressure common rail fuel system, comprising a host computer system, servo motor I, servo motor II, crankshaft signal disk, camshaft signal disk, and injection detector;

[0005] The output terminals of the host computer system are respectively connected to the input terminals of servo motor I and servo motor II. The number of injection detectors is the same as the number of injectors in the fuel system, and each injection detector is connected to its corresponding injector. The output terminal of the injection detector is connected to the input terminal of the host computer system. The output signal interface of the host computer system is connected to the ECU speed setting interface in the fuel system. The input terminal of the host computer system is connected to the output terminal of the rail pressure sensor on the common rail pipe in the fuel system.

[0006] The servo motor I is connected to the crankshaft signal disk, the crankshaft signal disk is meshed with the camshaft signal disk, a crankshaft speed sensor is installed on the crankshaft signal disk, the crankshaft speed sensor is connected to the ECU crankshaft speed interface in the fuel system, and a camshaft speed sensor is installed on the camshaft signal disk, the camshaft speed sensor is connected to the ECU camshaft speed interface in the fuel system.

[0007] The servo motor II is connected to the high-pressure oil pump in the fuel system and is used to drive the high-pressure oil pump.

[0008] As a preferred embodiment of the present invention, the host computer system includes a communication board, which is connected to servo motor I, servo motor II and injection detector.

[0009] As a preferred embodiment of the present invention, the host computer system includes a signal output board that can output a 4-20mA signal.

[0010] As a preferred embodiment of the present invention, the speed ratio of the camshaft signal disk to the crankshaft signal disk is 1:2.

[0011] As a preferred embodiment of the present invention, the crankshaft speed plate is in the same state as the diesel engine speed plate, the camshaft speed plate is in the same state as the diesel engine camshaft speed plate, and the phase relationship between the missing tooth on the crankshaft speed plate and the single magnetic nail on the camshaft speed plate is consistent with the actual state of the diesel engine.

[0012] An automatic detection method for an electronically controlled high-pressure common rail fuel system includes the following steps:

[0013] S1: Before the test begins, import the diesel engine operating curve, injector drive data, and the crankshaft and high-pressure oil pump drive shaft speed ratio, crankshaft speed disc tooth missing tooth and camshaft speed disc single magnetic nail phase relationship into the host computer system.

[0014] S2: The host computer sets the operating speed of servo motor I according to the diesel engine operating curve, simulates the crankshaft speed and camshaft speed of the diesel engine, and sets the operating speed of servo motor II according to the diesel engine operating curve and the speed ratio of crankshaft and high-pressure oil pump drive shaft. It outputs a 4-20mA signal to provide the set speed to the ECU according to the diesel engine operating curve.

[0015] S3: After the ECU detects that the crankshaft speed is greater than the set ignition speed, the camshaft timing signal is normal, and the rail pressure signal is normal, it adjusts the rail pressure to stabilize according to the set parameters and controls the injector to inject fuel.

[0016] S4: After the detection starts, the host computer system reads the real-time data of the injection detector, obtains the current real-time fuel injection quantity, and compares it with the theoretical fuel injection quantity under the current actual speed and power.

[0017] The host computer system detects and analyzes the actual speed and set speed of servo motor I in real time. Based on the relationship between the speed of servo motor I and the set speed, the speed adjustment capability of the ECU is evaluated according to the design requirements.

[0018] The host computer system monitors and analyzes the actual rail pressure and the set rail pressure in real time. Based on the relationship between the actual rail pressure and the set rail pressure, the ECU's rail pressure adjustment capability is evaluated according to the design requirements.

[0019] As a preferred technical solution of the present invention, the diesel engine operating curve in step S1 includes a set speed, a set power, a set rail pressure, and the theoretical fuel injection quantity at each speed and power.

[0020] As a preferred embodiment of the present invention, the injector drive data in step S1 includes peak current, boost current, holding current, boost current time and holding current time.

[0021] As a preferred technical solution of the present invention, in step S4, when the real-time fuel injection quantity is less than the theoretical fuel injection quantity, the servo motor I is controlled to reduce speed.

[0022] When the real-time fuel injection quantity is greater than the theoretical fuel injection quantity, control the servo motor I to increase its speed.

[0023] When the real-time fuel injection quantity equals the theoretical fuel injection quantity, the speed of servo motor I remains constant.

[0024] When the speed of servo motor I changes, the speed of servo motor II changes in real time according to the speed ratio.

[0025] As a preferred embodiment of the present invention, in step S4, when the real-time fuel injection quantity is consistent with the theoretical fuel injection quantity but the set speed is inconsistent with the actual speed, the fuel injection quantity deviation and the speed deviation are weighted and fused into a PID input, and the PID algorithm output is used as the servo motor output control quantity. The PID algorithm is as follows:

[0026]

[0027] -

[0028] in, For PID input signal, As for rotational speed weighting, Actual speed - target speed For fuel injection quantity weighting, Actual fuel injection quantity - theoretical fuel injection quantity This represents the current output of the servo motor. As a proportion, For integration, This is the cumulative sum of the overall deviations from the initial period to the current period. For differential, This represents the overall deviation from the previous period.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows: The automatic detection device and method for the electronically controlled high-pressure common rail fuel system provide the ECU with crankshaft simulated speed signals and camshaft simulated speed signals, enabling the ECU to operate its fuel injection function. It detects the actual fuel injection quantity in real time, and through an algorithm, feeds back the difference between the real-time injection quantity and the theoretical injection quantity, and the difference between the real-time speed and the set speed, to the target crankshaft speed and the actual crankshaft speed, enabling the ECU to operate its speed regulation function and evaluating its speed regulation capability. It also monitors the real-time rail pressure and the set rail pressure in real time, evaluating the ECU's rail pressure adjustment capability, thereby avoiding the risks of new product testing and reducing production costs. Attached Figure Description

[0030] Figure 1 This is a planar structural diagram of the present invention. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] like Figure 1 The present invention provides a technical solution: an automatic detection device for an electronically controlled high-pressure common rail fuel system, comprising a host computer system, servo motor I, servo motor II, crankshaft signal disk, camshaft signal disk, and injection detector;

[0033] The fuel system under test includes an ECU, a high-pressure fuel pump, a common rail, and fuel injectors. The fuel system under test is normally connected. The solenoid valve on the high-pressure fuel pump is connected to the fuel pump solenoid valve drive interface of the ECU. The rail pressure sensor on the common rail is connected to the rail pressure signal interface of the ECU. The fuel injectors are connected one-to-one with the fuel injector drive interfaces on the ECU.

[0034] The output of the host computer system is connected to the input signals of servo motor I and servo motor II respectively. The number of injection detectors is the same as the number of fuel injectors in the fuel system, and the injection detectors are connected to the corresponding fuel injectors. The output of the injection detectors is connected to the input signal of the host computer system. The output signal interface of the host computer system is connected to the ECU speed setting interface in the fuel system. The input of the host computer system is connected to the output of the rail pressure sensor on the common rail pipe in the fuel system.

[0035] The host computer system includes a communication board, which connects to servo motor I, servo motor II and the injection detector. The host computer system also includes a signal output board, which can output 4-20mA signals.

[0036] The host computer system sets the speed of servo motor I and servo motor II through communication, and reads the detection results of the jet detector through communication.

[0037] Servo motor I is connected to the crankshaft signal disk, and the crankshaft signal disk is meshed with the camshaft signal disk. The speed ratio between the camshaft signal disk and the crankshaft signal disk is 1:2.

[0038] Servo motor II is connected to the high-pressure oil pump in the fuel system and is used to drive the high-pressure oil pump.

[0039] The crankshaft speed plate is kept in the same state as the diesel engine speed plate. In this embodiment, a 60-2 tooth type is used. A crankshaft speed sensor is installed on the crankshaft signal plate, and the crankshaft speed sensor is connected to the ECU crankshaft speed interface in the fuel system.

[0040] The camshaft speed plate is consistent with the diesel engine camshaft speed plate. In this embodiment, a single magnetic nail method is used. A camshaft speed sensor is installed on the camshaft signal plate. The camshaft speed sensor is connected to the ECU camshaft speed interface in the fuel system.

[0041] The phase relationship between the missing tooth on the crankshaft speed dial and the single magnetic nail on the camshaft speed dial is consistent with the actual state of the diesel engine.

[0042] An automatic detection method for an electronically controlled high-pressure common rail fuel system includes the following steps:

[0043] S1: Before the test begins, import the diesel engine operating curve into the host computer system. The diesel engine operating curve includes the set speed, set power, set rail pressure, and theoretical fuel injection quantity at each speed and power.

[0044] Before the test begins, the testers import the injector drive data, including peak current, boost current, holding current, boost current time and holding current time, into the host computer system.

[0045] Before the test began, the testers set the crankshaft and high-pressure oil pump drive shaft speed ratio in the host computer system according to the actual configuration of the diesel engine.

[0046] Before the test began, the testers set the phase relationship between the missing teeth on the crankshaft speed plate and the single magnetic nail on the camshaft speed plate according to the actual configuration of the diesel engine and imported it into the ECU.

[0047] S2: Before the test begins, the host computer sets the operating speed of servo motor I according to the diesel engine operating curve to simulate the crankshaft speed and camshaft speed of the diesel engine. It also sets the operating speed of servo motor II according to the diesel engine operating curve and the speed ratio of crankshaft and high-pressure oil pump drive shaft. The host computer outputs a 4-20mA signal to provide the set speed to the ECU according to the diesel engine operating curve.

[0048] S3: After the ECU detects that the crankshaft speed is greater than the set ignition speed, the camshaft timing signal is normal, and the rail pressure signal is normal, it adjusts the rail pressure to stabilize according to the set parameters and controls the injector to inject fuel.

[0049] S4: After the detection starts, the host computer system reads the real-time data of the injection detector, obtains the current real-time fuel injection quantity, and compares it with the theoretical fuel injection quantity under the current actual speed and power. When the real-time fuel injection quantity is less than the theoretical fuel injection quantity, the system controls the servo motor I to reduce its speed. When the real-time fuel injection quantity is greater than the theoretical fuel injection quantity, the system controls the servo motor I to increase its speed. When the real-time fuel injection quantity is equal to the theoretical fuel injection quantity, the system maintains the speed of the servo motor I unchanged. When the speed of the servo motor I changes, the speed of the servo motor II changes in real time according to the speed ratio.

[0050] To avoid the servo motor failing to adjust to the target speed when the real-time fuel injection quantity matches the theoretical fuel injection quantity but the set speed differs from the actual speed during adjustment, this embodiment uses a weighted fusion of fuel injection quantity deviation and speed deviation as the PID input, and the PID algorithm output is used as the servo motor output control quantity. The algorithm used is as follows:

[0051]

[0052] -

[0053] in, For PID input signal, As for rotational speed weighting, Actual speed - target speed For fuel injection quantity weighting, Actual fuel injection quantity - theoretical fuel injection quantity This represents the current output of the servo motor. As a proportion, For integration, This is the cumulative sum of the overall deviations from the initial period to the current period. For differential, This represents the overall deviation from the previous period.

[0054] The host computer system monitors and analyzes the actual speed and set speed of servo motor I in real time. Based on the relationship between the speed of servo motor I and the set speed, the speed adjustment capability of the ECU is evaluated according to the design requirements.

[0055] After the test begins, the host computer system monitors and analyzes the actual rail pressure and the set rail pressure in real time. Based on the relationship between the actual rail pressure and the set rail pressure, the ECU's rail pressure adjustment capability is evaluated according to the design requirements.

[0056] After the test begins, the host computer system reads the real-time current waveform of the injection tester and compares it with the set injector drive data, including peak current, boost current, holding current, boost current time, and holding current time, to evaluate the ECU injector drive capability.

[0057] After the testing begins, the condition of the high-pressure oil pump and common rail is checked regularly. The condition of the high-pressure oil pump and common rail is evaluated through long-term operation.

[0058] The parts of the invention not described in detail are prior art. Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic detection device for an electronically controlled high-pressure common rail fuel system, characterized in that: Includes a host computer system, servo motor I, servo motor II, crankshaft signal disk, camshaft signal disk, and injection detector; The output terminals of the host computer system are respectively connected to the input terminals of servo motor I and servo motor II. The number of injection detectors is the same as the number of injectors in the fuel system, and each injection detector is connected to its corresponding injector. The output terminal of the injection detector is connected to the input terminal of the host computer system. The output signal interface of the host computer system is connected to the ECU speed setting interface in the fuel system. The input terminal of the host computer system is connected to the output terminal of the rail pressure sensor on the common rail pipe in the fuel system. The servo motor I is connected to the crankshaft signal disk, the crankshaft signal disk is meshed with the camshaft signal disk, a crankshaft speed sensor is installed on the crankshaft signal disk, the crankshaft speed sensor is connected to the ECU crankshaft speed interface in the fuel system, and a camshaft speed sensor is installed on the camshaft signal disk, the camshaft speed sensor is connected to the ECU camshaft speed interface in the fuel system. The servo motor II is connected to the high-pressure oil pump in the fuel system and is used to drive the high-pressure oil pump.

2. The automatic detection device for an electronically controlled high-pressure common rail fuel system according to claim 1, characterized in that: The host computer system includes a communication board, which is connected to servo motor I, servo motor II and the jetting detector.

3. The automatic detection device for an electronically controlled high-pressure common rail fuel system according to claim 1, characterized in that: The host computer system includes a signal output board that can output 4-20mA signals.

4. The automatic detection device for an electronically controlled high-pressure common rail fuel system according to claim 1, characterized in that: The speed ratio of the camshaft signal disk to the crankshaft signal disk is 1:

2.

5. The automatic detection device for an electronically controlled high-pressure common rail fuel system according to claim 1, characterized in that: The crankshaft speed plate is in the same state as the diesel engine speed plate, the camshaft speed plate is in the same state as the diesel engine camshaft speed plate, and the phase relationship between the missing tooth on the crankshaft speed plate and the single magnetic nail on the camshaft speed plate is consistent with the actual state of the diesel engine.

6. The detection method of the automatic detection device for an electronically controlled high-pressure common rail fuel system according to any one of claims 1-5, characterized in that: Includes the following steps: S1: Before the test begins, import the diesel engine operating curve, injector drive data, and the crankshaft and high-pressure oil pump drive shaft speed ratio, crankshaft speed disc tooth missing tooth and camshaft speed disc single magnetic nail phase relationship into the host computer system. S2: The host computer sets the operating speed of servo motor I according to the diesel engine operating curve, simulates the crankshaft speed and camshaft speed of the diesel engine, and sets the operating speed of servo motor II according to the diesel engine operating curve and the speed ratio of crankshaft and high-pressure oil pump drive shaft. It outputs a 4-20mA signal to provide the set speed to the ECU according to the diesel engine operating curve. S3: After the ECU detects that the crankshaft speed is greater than the set ignition speed, the camshaft timing signal is normal, and the rail pressure signal is normal, it adjusts the rail pressure to stabilize according to the set parameters and controls the injector to inject fuel. S4: After the detection starts, the host computer system reads the real-time data of the injection detector, obtains the current real-time fuel injection quantity, and compares it with the theoretical fuel injection quantity under the current actual speed and power. The host computer system detects and analyzes the actual speed and set speed of servo motor I in real time. Based on the relationship between the speed of servo motor I and the set speed, the speed adjustment capability of the ECU is evaluated according to the design requirements. The host computer system monitors and analyzes the actual rail pressure and the set rail pressure in real time. Based on the relationship between the actual rail pressure and the set rail pressure, the ECU's rail pressure adjustment capability is evaluated according to the design requirements.

7. The automatic detection method for an electronically controlled high-pressure common rail fuel system according to claim 6, characterized in that: The diesel engine operating curve in step S1 includes the set speed, set power, set rail pressure, and theoretical fuel injection quantity at each speed and power.

8. The automatic detection method for an electronically controlled high-pressure common rail fuel system according to claim 6, characterized in that: The injector drive data in step S1 includes peak current, boost current, holding current, boost current time and holding current time.

9. The automatic detection method for an electronically controlled high-pressure common rail fuel system according to claim 6, characterized in that: In step S4, when the real-time fuel injection quantity is less than the theoretical fuel injection quantity, the servo motor I is controlled to reduce its speed. When the real-time fuel injection quantity is greater than the theoretical fuel injection quantity, control the servo motor I to increase its speed. When the real-time fuel injection quantity equals the theoretical fuel injection quantity, the speed of servo motor I remains constant. When the speed of servo motor I changes, the speed of servo motor II changes in real time according to the speed ratio.

10. The automatic detection method for an electronically controlled high-pressure common rail fuel system according to claim 6, characterized in that: In step S4, when the real-time fuel injection quantity is consistent with the theoretical fuel injection quantity but the set speed is inconsistent with the actual speed, the fuel injection quantity deviation and speed deviation are weighted and fused into a PID input, and the output is used as the servo motor output control quantity through the PID algorithm. The PID algorithm is as follows: - in, For PID input signal, As for rotational speed weighting, Actual speed - target speed For fuel injection quantity weighting, Actual fuel injection quantity - theoretical fuel injection quantity This represents the current output of the servo motor. As a proportion, For integration, This is the cumulative sum of the overall deviations from the initial period to the current period. For differential, This represents the overall deviation from the previous period.

Images